Diathermy device



. 1,628 806 17 1927' F. H. REIJNDERS I DIATHERMY DEVICE Filed Oct. 8,1923 7221 R e zljn er Patented May 17, 1.9.27.

UNITED- STATES FATE "r r ce.

rmmcrscus r nnaicus REIJNDERTS, or SO'ESTERIBERG, NETHERLANDS, assienoa01: -ONE-HALIE '.EO.1\]AAMLOOZE VENNOOTSCHAP NEDERLANDSCHE sEmroEsrELLENFABRIEK, OF'HILVERSUM,'NETHERLA-NDS.

DIATHERMY DEVICE.

' Applicatioafi led October's, 1923, Serial m. 667,371,311: intheltetherlands 0ctoberi6, 1922.

The present invention relates to apparatuses and devices for locallygenerating heat, e. g. in living organisms fluids and similarelectrically conductive media.

To this end high frequency alternating currents are generated by meansof a triode or valve, of which the grid and the anode are each connectedto the glowing filament by nieans of a conductor whilst their circuitsare electrically connected to each other. A high tension source ofcurrent isxincluded between the anode and the cathode and the cathode issupplied from a source of current. The frequency of the generatedalternatin r currents is determined by the electricconstants of the saidcircuit. The quantity of energy which may be taken from this a ratus maybe varied by coupling a third cuit electrically to one of the two saidcuits and by bringing the be treated Oil.- cirobject or body to in thesaid third circuit.

The principal characteristic of the invention is that means are providedwhich completely control and regulate the Various physiologicalphenomena to which the patient is subjected, in accordance with thedisease and the sensitiveness of the patient.

Said means are partially contained in the oscillation-generator andpartially in the electrode. Thereby it is rendered possible to vary notonly the intensity of the oscillations and the frequency, but also thetemperature of the electrode and its chemical actions. As is known thevery high frequencies cause the so-called skin efi'ect, which consiststherein that the alternating currents pass exclusively through theperiphery of the conducting body. For certain purposes for instance forsurgical purposes, this may be of great advantage; for other purposesfor instance for mere depth heating it is however a disadvantage as inthat case it is desired to operate at a lower frequency. 4 In connectionerewith it is pointed out that the said conducting bodies enerally havea very small inductance whic will only occur in a high degree whenoperating at very high frequency.

Further the device is so constructed that it may be connected to theordinary electric lighting circuit whereby its value for a physician isincreased. Also may easily be vders it possible .backs are causes thatthe skin effectan X-ray tube par-' ticularly of the Coolidge typeconnected thereto so that the physician need not buy a special X-raydevice.

A further characteristic of the device consists in the particulargrounding which renthatthe physician may touch the patient without,danger of shocks. Further irritation phenomena areprevented or regulatedby transmitting the generated alternating current to the human body. bymeans of a special electrode.

The electrodes hitherto used consisted of a conducting object, which wasbrought into contact with the skin. The conducting sur face usuallyconsisted of metal, sometimes of a layer of some material an electrolyteand thus made conductive. As the point of contact always shows a greatcontact-resistance, a great quantity of heat will be reduced at thespot, soon causing the elec'troce to get a higher temperature than isdesirable. Particularly in applying oscillations of a very highfrequency this heating will take place at the edges, as in consequenceof the so-called skin effect the current is pressed to the outside ofconducting bodies. This causes at the same time disagreeable irritationphenomena at the places of contact. These drawbacks of the electrodesused hitherto were the reasons that certain diseases couldnotsatisfactorily be treated diathermically and particularly in thosecases, where a large supply of energy was necessary, no favourableresults could be obtained, such as, for example, with urethritisgonorrhoeica.

According to the invention these drawovercome by using -an electrode,which is made of an alloy of various metals, which electrode isintensively cooled at the edges. This can for-example be obtained byapplying a bent tube round the edge, through which edge acooling fluidmay pass with such a rapidity'that the desired temperature is maintainedconstantly.

Moreover it is possible to avoid irritation phenomena by asuitablechoice of the electrode material. material should not only conduct theelectric current well and should be at the same time agoodheat-conductor, but that the electrode material should bemechanically soft. Various metals, especially those with a. low melting.point are suitable for the purpose, such or other, soaked in- It hasappeared that suchas Woods-metal, tin, antimony and various whereas,copper appeared to he peculiarly unsuitable.

In this connection it maybe observed am for open-wound treatment, themetals must he totally dill'erent. It has been found that in that ea:.e.preference must. be given to precious metals. c

The devieemay further be provided with a safety device whichautonnitically takes care. that. the temperature oi? thepart of the bodyto he treated is kept within predetermined limits. For instance theremay be connected to the electrode a device, the electric properties ofwhich vary in a known manner according to a temperature and which deviceacts upon the oscillation-generating, the coupling or the cooling of theelectrode. i i To better understand the nature of the invention apreferred form of a connection.

'25 to be used with the'apparatus will he described with reference tothe accompanying drawing inwhich :Figure 1 is a diagram of the. electriccircuit. :10 Figures 2 and 3 are side and plan view, respectively, ofthe fluid cooled electrode.

Figure 4 is a Fig. 3.

The current is supplied by couductors 1 and 2 from an ordinaryalternating-current lighting-plant. Part of this current passingthrough'the transformer supplies the fila ment of thetriode, which isearthed at 25. Another part of the current is supplied to transformer 4and passes two circuit controllers 5 and 6 of whichthe former is asafety-contact which is closed, when the ca e containing thehigh-tension-apparatuses is closed, making it impossible to touch theseparts, when working. The controller 0 is of the foot operated type bywhich the physician is enabled, either to connect the apparatus for ashort time or for an indefinite period. A condenser 7 connected acrossthe secondary of the liigh-tension-transformer 4. One end of thesecondary wind ingis connected through a high-frequency choking-coil 8to the valve, whereas the other extremity. of the secondary'is connectedto, earth through a milliammeter 9, so that with this meter theanode-current can he measured. The coil 8 prevents high-frequencyalternating-currents from reaching the transformer 4, whilst theimpedance of coil 8' together with the react-ance of the con-- denser 7'prevents the secondary current-of transformer 4 from passingthrough-con.- denser 10 to earth. The generated hlgh frequencycu'rrentscan pass the condenser 10,.

which, however, does not allow the rectified section on.the line Al3 oftensity of the purealternating current generated in this'circuit. Thevalve. is connected in a very special-way withthe oscillatioi'i-circuit.The grid of the valve is connected with leakage-res:stance 16 Vlfifl.gridcondenser 15, to the one extremity of coil 11, whereas the filamentwhich-1s earthed, is con nected with point 17 of tlns coil. The anode orplate of the valve is connected with the coil 11 inductively as well asdirectly; inductively by means' of coil 18, which possesses as a rulemany windings of thin wire and the extremity of which is directlyconnected to point 1 of coil 11. By this device and a good so action ofthe points 19 and 17' numerous experiments have shown,

that the energy used can suddenly be altered within wide ranges withoutthe valve ceasing to generate. 'so that a continued uninterruptedmedical treatment is possible, which is of the utmost importance for themedical results.

The energy used is taken off in this pling-coil 20. The current ledthrough the conductors 21 and-22 is read on the amperemeter 23; at 24 anearth connection is provided, which enables the physician to touch thepatient without danger of shocks.

In some cases it is desirable to provide a device, whereby thetemperature of the electrode or the treated part of the body is keptconstantly within certain limits.

'For thi's'purpose the electrode an embodiment of which is illustratedin Figures 2, 3 and 4, is provided with a device for regulating thetemperature which is formed by a bent metal tube 26 forming the rim ofthe ellectrodc and through which a cooling liquid 1' ows.

The two halves of the tube are interconnected by means of the plate 27of electrode material which is clamped. around the tube as is shown inthe Figures 3 and 4.

The necessary firmness may be obtained by the parts 28, shown in Fig. 2which are hingedly connected together at 29 so as to allow somedeformation of the electrode.

lit)

The electrode mav by means of resilient sleeves 30 be attached flexiblyto a belt or directly by the relay springs, but it is obvious that inmostcases special switches using condensers-or resistances across theircontacts W111 be necesshy.

Finally the new apparatus can be applied for physiologic-neurologic andpathologicneurologic research inconnection with the extensivevariability of the oscillating-frequency, whereby the great advantage isobtained that the irritability as a function of theoscillation-frequency can be expressed in numbers directly.

Although in this specification the applications for medical purposes areplaced on the foreground, it is evident that the use of the apparatus isnot restricted to these applications but that it can be utilizedeverywhere with great advantage in all such cases, where a local heatingis required without that electrolyzearises, especially for'industrial,chemical and bacteriological purposes.

I claim 1. A device for diathermy comprising in combination means forgenerating hi h fre- 'quency currents of constant intenslty including atrlode and means for ma1nta1n that with a strongly changing load thegenerating of the apparatus is not interrupted.

3. Device for diathermy comprising in combination, means for generatinghigh frequency currents of constant intensity intherebythat a metallictube the cooling liqu1d flows is arranged around eluding a triode and anelectrode with edges.

that may be cooled during the treatment through which the-edge. a

4. Device for diathermy comprising in combination means for generatinghigh frequency currents including a triode and an electrode, entirely orpartially made of a metal or an alloy of low degree. of hardness, whichbelongs to the tin group or is an alloy of metals 0 this group, theedges of which may be cooled during the'treatment.

'5. Device for diathermy comprising in combination means for generatinghigh frequency currents including a triode, an electrode,-meansassociated with the electrode in such a manner that the resistance, orthermoelectric force of said means varies with the temperature of thesaid electrode and controls the energy supply to or the heat dischargefrom the electrode.

6. Device for diathermy comprising in combination means for generatinghigh frequency current including a triode, two elec trodes, aninductively coupled coil connected with the two electrodes, one end ofsaid coil being grounded.

7. Device for diathermy comprising in combination means for generatinghigh fre quency currents including a triode, a coupling coil inductivelycoupled to said means and aRontgen tube connected to said coupling coilsIn testimony whereof I afiix my signature. i

'FRANCISCllS HENRICUS' REIJNDERS.

